#include "common.h"

extern char *print_number_lu_r(char *str, unsigned long uvalue);
extern char *print_number_llu_r(char *str, unsigned long long uvalue);

storage_number pack_storage_number(calculated_number value, uint32_t flags)
{
    // bit 32 = sign 0:positive, 1:negative
    // bit 31 = 0:divide, 1:multiply
    // bit 30, 29, 28 = (multiplier or divider) 0-6 (7 total)
    // bit 27, 26, 25 flags
    // bit 24 to bit 1 = the value

    storage_number r = get_storage_number_flags(flags);
    if(!value) return r;

    int m = 0;
    calculated_number n = value;

    // if the value is negative
    // add the sign bit and make it positive
    if(n < 0) {
        r += (1 << 31); // the sign bit 32
        n = -n;
    }

    // make its integer part fit in 0x00ffffff
    // by dividing it by 10 up to 7 times
    // and increasing the multiplier
    while(m < 7 && n > (calculated_number)0x00ffffff) {
        n /= 10;
        m++;
    }

    if(m) {
        // the value was too big and we divided it
        // so we add a multiplier to unpack it
        r += (1 << 30) + (m << 27); // the multiplier m

        if(n > (calculated_number)0x00ffffff) {
            error("Number " CALCULATED_NUMBER_FORMAT " is too big.", value);
            r += 0x00ffffff;
            return r;
        }
    }
    else {
        // 0x0019999e is the number that can be multiplied
        // by 10 to give 0x00ffffff
        // while the value is below 0x0019999e we can
        // multiply it by 10, up to 7 times, increasing
        // the multiplier
        while(m < 7 && n < (calculated_number)0x0019999e) {
            n *= 10;
            m++;
        }

        // the value was small enough and we multiplied it
        // so we add a divider to unpack it
        r += (0 << 30) + (m << 27); // the divider m
    }

#ifdef STORAGE_WITH_MATH
    // without this there are rounding problems
    // example: 0.9 becomes 0.89
    r += lrint((double) n);
#else
    r += (storage_number)n;
#endif

    return r;
}

calculated_number unpack_storage_number(storage_number value)
{
    if(!value) return 0;

    int sign = 0, exp = 0;

    value ^= get_storage_number_flags(value);

    if(value & (1 << 31)) {
        sign = 1;
        value ^= 1 << 31;
    }

    if(value & (1 << 30)) {
        exp = 1;
        value ^= 1 << 30;
    }

    int mul = value >> 27;
    value ^= mul << 27;

    calculated_number n = value;

    // fprintf(stderr, "UNPACK: %08X, sign = %d, exp = %d, mul = %d, n = " CALCULATED_NUMBER_FORMAT "\n", value, sign, exp, mul, n);

    while(mul > 0) {
        if(exp) n *= 10;
        else n /= 10;
        mul--;
    }

    if(sign) n = -n;
    return n;
}

int print_calculated_number(char *str, calculated_number value)
{
    char *wstr = str;

    int sign = (value < 0) ? 1 : 0;
    if(sign) value = -value;

#ifdef STORAGE_WITH_MATH
    // without llrint() there are rounding problems
    // for example 0.9 becomes 0.89
    unsigned long long uvalue = (unsigned long long int) llrint(value * (calculated_number)100000);
#else
    unsigned long long uvalue = value * (calculated_number)100000;
#endif

#ifdef ENVIRONMENT32
    if(uvalue > (unsigned long long)0xffffffff)
        wstr = print_number_llu_r(str, uvalue);
    else
        wstr = print_number_lu_r(str, uvalue);
#else
    do *wstr++ = (char)('0' + (uvalue % 10)); while(uvalue /= 10);
#endif

    // make sure we have 6 bytes at least
    while((wstr - str) < 6) *wstr++ = '0';

    // put the sign back
    if(sign) *wstr++ = '-';

    // reverse it
    char *begin = str, *end = --wstr, aux;
    while (end > begin) aux = *end, *end-- = *begin, *begin++ = aux;
    // wstr--;
    // strreverse(str, wstr);

    // remove trailing zeros
    int decimal = 5;
    while(decimal > 0 && *wstr == '0') {
        *wstr-- = '\0';
        decimal--;
    }

    // terminate it, one position to the right
    // to let space for a dot
    wstr[2] = '\0';

    // make space for the dot
    int i;
    for(i = 0; i < decimal ;i++) {
        wstr[1] = wstr[0];
        wstr--;
    }

    // put the dot
    if(wstr[2] == '\0') { wstr[1] = '\0'; decimal--; }
    else wstr[1] = '.';

    // return the buffer length
    return (int) ((wstr - str) + 2 + decimal );
}
